U.S. Pat. No. 2,889,038 (Kalleberg) discloses a linerless double-coated pressure-sensitive adhesive tape wound upon itself in roll form and comprising a flexible support having on opposite faces chemically different and physically incompatible pressure-sensitive adhesives. Although the Kalleberg patent calls both layers "aggressively tacky", the patented linerless transfer tape is not currently used when high performance is required. Even though Kalleberg tapes are currently on the market, it is believed that at the present time all high-performance double-coated pressure-sensitive adhesive tapes are wound up with disposable, low-adhesion liners.
Applicant is not aware of any linerless double-coated pressure-sensitive adhesive tape other than that of Kalleberg and is not aware of any product incorporating Kalleberg's tape except the simple linerless tape now on the market as described in the patent.